Space is a pretty dark place. Some areas are more darker than others. Among them Black holes are the darkest. Black holes is an area of such unbelievable gravity centralized in to one single point. So from that reagan of space nothing can escape, not evan a light. The point that all matter trapped is called singularity, it might be infinity small, but influence is enormous. Due to the enormous gravity there is a region of space around the singularity that light cannot escape. it’s called event horizon. Event horizon is the the outer boarder of a black hole. If someone fall in to the black hole he will spaghettify breaking in to smallest atom.